Laser etching of glass substrates by 1064 nm laser irradiation

Glass substrates are transparent to 1064 nm laser irradiation and cannot be etched directly by 1064 nm pulsed laser. By placing the glass substrate in contact with copper sulphate (CuSO4) solution and irradiating 1064 nm laser light through the glass, etching of the glass is observed on the downside of the glass, the contact side with the copper sulphate solution. The etching mechanism is proposed to be a two-step process. The first step is the deposition of copper from copper sulphate solution upon 1064 nm irradiation. It is followed by the absorption of the 1064 nm laser irradiation by the deposited copper, resulting in the etching of the glass. Using this technique, 1 mm thick soda lime glass slides can be cut through. Furthermore, various arbitrary shapes can be diced out from glass substrates. The formation of copper deposits is observed and characterized.